Clin Cancer Res
-
A Phase I study was performed to determine the maximum tolerated dose (MTD), toxicities, and pharmacokinetic profile of irinotecan (CPT-11) and its active metabolites when given on a once-every-3-week schedule. Thirty-four patients with advanced refractory solid malignancies were treated with CPT-11 (240-340 mg/m2) administered as a 90-min i.v. infusion every 3 weeks. Patients were divided into two groups: those with and those without prior abdominal/pelvic (AP) radiotherapy. ⋯ In conclusion, gastrointestinal toxicity and hematological toxicity were the dose-limiting toxicities of CPT-11 when administered as a 90-min infusion every 3 weeks. In this trial, the recommended Phase II starting dose for patients with no prior AP radiation therapy was found to be 320 mg/m2; for patients with prior AP radiation, the recommended Phase II starting dose was 290 mg/m2. This once-every-3-week schedule has been incorporated into a Phase I trial of CPT-11 combined with 5-fluorouracil and leucovorin.
-
Coordinated presentation of antigen and costimulatory molecules has been shown to result in the induction of an antigen-specific T-cell response rather than the development of anergy. This study evaluated the vaccine ALVAC-CEA B7.1, a canary pox virus that has been engineered to encode the gene for the tumor-associated antigen carcinoembryonic antigen (CEA) and B7.1, a T-cell costimulatory molecule. Patients with CEA-expressing tumors were immunized with 2.5 x 10(7) (n = 3), 1.0 x 10(8) (n = 6), and 4.5 x 10(8) (n = 30) plaque-forming units intradermally every other week for 8 weeks. ⋯ After four vaccinations, patients who were HLA-A-2-positive demonstrated increases in their CEA-specific T-cell precursor frequencies to a CEA-A2-binding peptide from baseline. The number of prior chemotherapy regimens was inversely correlated with the ability to generate a T-cell response. ALVAC-CEA B7.1 is safe in patients with advanced, recurrent adenocarcinomas that express CEA, and it is associated with the induction of a CEA-specific T-cell response.
-
The antitumor effects of the selective cyclooxygenase (COX)-2 inhibitor SC-236 alone and in combination with radiation were investigated using the human glioma cell line U251 grown in monolayer culture and as tumor xenografts. On the basis of Western and Northern blot analyses, these cells express COX-2 protein and mRNA to levels similar to those in the human colon carcinoma cell line HT29. Treatment of U251 cells in monolayer culture with 50 microM SC-236 resulted in a time-dependent decrease in cell survival as determined by a clonogenic assay. ⋯ To extend these investigations to an in vivo situation, U251 glioma cells were grown as tumor xenografts in the hind leg of nude mice, and SC-236 was administered in drinking water. SC-236 alone slowed tumor growth rate, and when administered in combination with local irradiation, SC-236 caused a greater than additive increase in tumor growth delay. These in vitro and in vivo results suggest that the selective inhibition of COX-2 combined with radiation has potential as a cancer treatment.